Metal-air batteries are usually primary cells, i.e. electrically non-rechargeable galvanic cells which produce a certain electrical voltage due to a chemical reaction of the respective metal with atmospheric oxygen. Such a primary cell can also be designated as fuel cell. Unlike primary cells, secondary cells are so-called rechargeable batteries which can be electrically recharged.
An exemplary structure for a zinc-air battery is known from WO 2012/156972 A1.
A zinc electrode for use in a rechargeable battery is known from WO 2013/150519 A1.
Known from WO 2013/128445 A1 is a metal-air battery in which spent fuel, namely zinc, is removed with the aid of a liquefier.
It is known from WO2013/150520 A1 for a metal-air battery to flush an electrolyte with a washing solution to transfer the battery into a standby mode.
It is known from WO 2013/150521 A1 for a metal-air battery to renew an electrolyte as required.
It is known from WO 2014/009951 A1 to couple a metal-air battery to a rechargeable electrical energy storage device, i.e. a rechargeable battery in such a manner that varying power requirements are met by a corresponding distribution of the power requirement to the metal-air battery and the respective rechargeable battery. By this means the metal-air battery is buffered with the rechargeable battery and the metal-air battery can be operated in a relatively constant manner since power fluctuations can be compensated by the rechargeable battery.
Controls for chargeable batteries are known from DE 11 2010 002 707 T5, from DE 11 2009 000 223 T5, from DE 10 2011 002 549 A1, from DE 10 2013 107 033 A1 and from DE 24 17 571 A.
A redox-flow battery is known from WO 99/39397 A1 in which ion exchange membranes of a plurality of battery cells which are combined into a cell stack are exposed to a positive half-cell electrolyte on the one hand and to a negative half-cell electrolyte on the other hand.
Metal-air batteries can be of great interest for use in electric vehicles since they have a very high chemical energy density. With the aid of these metal-air batteries, the range of an electric vehicle can be increased significantly compared with rechargeable batteries.
A problem with metal-air batteries is the implementation of a power control which enables a dynamic adaptation, suitable for the vehicle, of the electrical energy which can be delivered with the aid of the metal-air battery, to the electrical energy actually required by the vehicle. In vehicles with electric-motor drive, the required electrical energy is subjected to severe fluctuations which result from the usually non-steady-state driving mode.
If the metal-air battery is designed for a high power, the lifetime of the battery is reduced even when only comparatively little power is required. Accordingly a complex power control is usually required, e.g. combined with a rechargeable battery as power buffer.